Question

我的表格如下：

Ride_distance    Ride_type
100              A         
50               B        
25               B       
25               C           
10               C          
40               A         
...              ...

现在我希望将每种类型的所有距离都计算出来并显示如下：

Tot_Type_A  Tot_Type_B  Tot_Type_C
140         75          35

我该怎么做？

Answer 1

  SELECT SUM(Ride_distance), Ride_type
    FROM your_table
GROUP BY Ride_type

Answer 2

从分组开始：

SELECT SUM(Ride_distance),Ride_type FROM rides GROUP BY Ride_type

如果您必须将它们放在同一行，请使用pivot：

SELECT 'TotalRide' as Total_Ride_Length, [A], [B], [C]
FROM
(SELECT Ride_distance, Ride_type FROM rides) AS SourceTable
PIVOT (
    SUM(Ride_distance) FOR Ride_type IN ([A], [B], [C])
) AS PivotTable;

Answer 3

是的，有可能，但你必须为每种类型写一个case语句：

select 
 sum(case ride_type when 'A' then ride_distance else 0 end) as tot_type_A,
 sum(case ride_type when 'B' then ride_distance else 0 end) as tot_type_B,
 sum(case ride_type when 'C' then ride_distance else 0 end) as tot_type_C
from your_table

Answer 4

使用PIVOT;

select 
    A as Tot_Type_A,
    B as Tot_Type_B,
    C as Tot_Type_C
from 
    dbo.the_table
pivot (
    sum(Ride_distance) for Ride_type in ([A],[B],[C])
) pvt

如何在新列中使用SUM的输出？

4 个答案: